1-Methylethyl Octanoate, a New Lepidopteran Sex Pheromone from the Bagworm, Megalophanes viciella

Extracts obtained by rinsing the thorax and extracts from the tergal sex pheromone gland of females of the bagworm moth, Megalophanes viciella, as well as headspace samples from live animals, were analyzed to reveal the chemical structure of the pheromone. As a result, 1-methylethyl octanoate was established as a main sex pheromone component of this species. This was further confirmed by numerous catches of conspecific males in traps baited with this compound in Bulgaria and Roumania.     

Preparation of graded index plastic rods doped with Sm3+ by interfacial-gel polymerization

A novel graded index (GI) poly(methyl methacrylate) (PMMA) rod was prepared by interfacial-gel polymerization carried out in a PMMA tube with one closed end. Bromobenzene (BB), a higher refractive index molecule, was used to obtain a graded index distribution and samarium octanoate (SOA) was used as a dye with Sm³⁺ concentrations from 60ppm to 700ppm. For a poly-merization system containing methyl methacrylate (MMA) as monomer, azobis-isobutyronitrile (AIBN) as initiator and dodecyl mercaptan as chain transfer agent, the difference of the refractive index from the centre to the periphery of the rod (Δn) with various BB and Sm³⁺ contents was determined. Experimental results showed that a parabolic profile of refractive index formed on the cross-section of the rod and Δn increased with increase of BB content. SOA has little effect on the profile within the given concentrations. The GI distribution may be calculated by free volume theory. The result is identical with the experimental distribution. © 1998 SCI.     

溴苯腈辛酸酯原药中主要杂质的GC/MS定性研究

利用气相色谱 -质谱联用仪对除草剂溴苯腈辛酸酯原药中所含主要杂质进行了定性研究 ,通过质谱图推断出主要杂质及其结构 ,合成杂质标样 ,由保留时间及质谱图确认了所推断的杂质组成和结构。     

Nanostructure and reactivity of carbon particles from co-pyrolysis of biodiesel surrogate methyl octanoate blended with n-butanol

This paper presents nanostructure and reactivity of carbon particles (soot) from co-pyrolysis of biodiesel surrogate methyl octanoate blended with n-butanol at temperatures from 1023 K to 1223 K in a quartz tube flow reactor, as n-butanol concentration increases from 0 to 50% (mole fraction) in the mixed fuels. The soot structure was characterized by low and high resolution transmission electron spectroscopy (LRTEM and HRTEM) and X-ray diffraction (XRD). The soot reactivity was investigated by thermogravimetric analyzer (TGA). When the pyrolysis temperature increased, as well as the rise of n-butanol addition, soot presented the higher degree of graphitization with the larger fringe length and lower fringe tortuosity. TGA results revealed that the higher amount addition of n-butanol can induce the formations of less reactive soot, and soot yielded at lower temperatures was more reactive than that at high temperatures. In addition, the high correlations between soot reactivity with its nanostructure were given in details.     

Sex Pheromone of <Emphasis Type="Italic">Elater ferrugineus</Emphasis> L. (Coleoptera: Elateridae)

The rare European click beetle, Elater ferrugineus L., develops exclusively in old, hollow deciduous trees. As a result of massive habitat loss caused by modern forestry, it is threatened throughout its entire distribution range and regarded as an indicator species for undamaged natural forests. As E. ferrugineus lives cryptically and its populations are frequently overlooked, we investigated its sex pheromone to develop a reliable detection tool. Pheromone gland extracts of single female E. ferrugineus were examined by using gas chromatography–mass spectrometry (GC–MS). All samples contained 7-methyloctyl 5-methylhexanoate, 7-methyloctyl octanoate, 7-methyloctyl 7-methyloctanoate, and 7-methyloctyl (Z)-4-decenoate in a ratio of approximately 1:1:3:3. Structures of all four esters, which have not been reported as pheromone compounds before, were confirmed by synthesis. A blend of the components was tested in the field and proved to be attractive for E. ferrugineus males, which were found to swarm exclusively during the day. This blend provides a noninvasive and effective monitoring method for this cryptic species, promising future collection records of E. ferrugineus in regions where it exists below the limit of detection by conventional collecting methods.     

Effect of sodium octanoate on the tribocorrosion behaviour of 5052 aluminium alloy

ABSTRACT

The 5000 series aluminium alloys are commonly used in a marine application where it is exposed to environments containing the chloride ions, which cause corrosion of aluminium alloy. The situation becomes even worse when aluminium alloys, in some situations, may suffer from combined corrosion and wear actions. The present study has been carried out to investigate the effect of sodium octanoate as a corrosion inhibitor on the corrosive wear behaviour of aluminium alloy 5052 in 0.5?M NaCl solution as simulated seawater. The effects of electrochemical potentials on the corrosive wear performance are also discussed.     

A lamellar liquid crystal with a vegetable oil

The molecular arrangement was studied in the sodium octanoate and cetyltrimethylammonium bromide (CTAB) system, a lamellar liquid crystal, before and after the addition of a vegetable oil [refined, bleached and deodorized (RBD) palm olein] by means of small-angle x-ray diffraction and optical microscopy. Results from the small-angle x-ray showed the RBD palm olein molecules to be partitioned between the nonpolar methyl group layers for both systems. The water molecules, located between the polar head groups, showed less penetrating tendency into the layered structure of cationic surfactant than into the anionic one, both before and after addition of RBD palm olein.     

20%硝·烟·辛酰溴可分散油悬浮剂高效液相色谱分析

采用高效液相色谱法,以乙腈和水为流动相(磷酸调制弱酸性液体),使用ZORBAX Eclipse Plus C_8色谱柱和紫外可变波长检测器,在245 nm波长下对20%硝·烟·辛酰溴可分散油悬浮剂进行定量分析。结果表明:硝磺草酮、烟嘧磺隆和辛酰溴苯腈的线性相关系数分别为0.999 7、0.999 7、0.999 6,标准偏差分别为0.064、0.021、0.079,变异系数分别为0.80%、0.53%、0.99%,平均回收率分别为100.18%、100.03%、99.85%。     

具有杀虫活性蔗糖酯的合成

分别以酯交换法和酰氯法合成了辛酸蔗糖酯和己酸蔗糖酯两种杀虫活性蔗糖酯,其中酯交换法产物单酯含量高,而酰氯法反应速度快。实验在n(蔗糖):n(辛酸乙酯)=2:1,DMF为溶剂,碳酸钾为催化剂,(98±2)℃条件下反应16 h制备了辛酸蔗糖酯,辛酸乙酯的转化率为68．5％(多酯按二酯计算,下同);在n(蔗糖):n(己酰氯)=2:1,DMF为溶剂、吡啶为助剂,65℃条件下反应1．5 h制备了己酸蔗糖酯,己酰氯的转化率为53．9％。产物经傅里叶红外光谱分析、薄层层析分离和分光光度分析,确定辛酸蔗糖酯和己酸蔗糖酯中n(单酯):n(多酯) 分别为1．48:1和1．37:1。以P(辛酸蔗糖酯)=4 mg／mL水溶液对舞毒蛾(Lymantria dispar)1龄幼虫进行杀虫实验,触杀方式36 h后校正死亡率达72．5％。     

除草剂辛酰溴苯腈的杂质分析

分析了辛酰溴苯腈生产中可能存在的杂质辛酰氯、溴苯腈醋酸酯、氯苯腈辛酰酯对药效的影响,并通过实验找到了避免这些杂质产生的方法,从而提高了辛酰溴苯腈产品质量。